The service was child-friendly, with plenty of babies, a Sunday school performance and young choristers, but baby George was not with the Royal couple at St Andrew's Cathedral.

In what was essentially a private Easter Day visit to church, members of the media were not allowed inside the Cathedral but waited with the thousands of people outside for a glimpse of the Royal Couple.

Prime Minister Tony Abbott arrived minutes before the Duke and Duchess of Cambridge, who were met by Archbishop Glenn Davies and the Dean of Sydney, Phillip Jensen.

Once inside, at the couple's request,  they saw not a special Royal service, but a regular Easter Sunday celebration complete with babies going into and out of the crying room, the Sunday school performing songwriter Colin Buchanan's 'He died upon the cross' and a dramatic reading by members of the St Andrew's Youth group.

The cathedral choir, with the youngest member just 7, sang Handel's Hallelujah Chorus and led the hymn singing.

Archbishop Glenn Davies spoke on the raising of Lazarus, and compared the miracle with Jesus' own death and resurrection.

"I've often wondered what it would have been like to have gone to the second funeral of Lazarus" the Archbishop said. "Imagine what kind of joy there would have been at that funeral. The mournful tears and yes, the loss of a brother but knowing that he would rise again and knowing for a certainty, for a surety, because he had already re-enacted a rising back into this world but now that Jesus has risen from the dead what a glory it is, what a perfection, what a wonder, what a miracle of salvation...."

After the service, the Duke and Duchess added their signatures to the Royal family members who have signed the First Fleet bible and prayer book, carried by chaplain Richard Johnson in 1788 and kept in a museum in St Philip's, York St.

After speaking to the members of the choir and Sunday school, the Royal Couple left for Taronga Zoo.